The present invention relates to a new and improved method of treating waste paper for obtaining a stock suspension for the production of new paper, and further, relates to novel apparatus for the performance of the aforesaid method.
Heretofore, waste paper, in order to obtain stock suspensions for the fabrication of new paper, has been dissolved in so-called stock slushers or pulpers, and heavy contaminants are eliminated in the pulper. The obtained liquid is removed through a sieve or screen from the stock slusher, refined and cleaned in a number of working operations, and thereafter introduced, for instance, into the tub or vat of a papermaking machine. Apart from the danger of clogging the sieve at the stock slusher, by not completely comminuted plastic particles and plastic foils, this procedure further has the drawback, that with great expenditure of energy, all of the constituents of the waste paper must be comminuted in such a fashion that they are able to pass through the sieve. However, at the same time there is rendered more difficult their separation capability from the suspension. This in turn leads to a large expenditure of energy and equipment costs.